A study published this week in JAMA Pediatrics reported that women were less likely to meet the recommended weekly requirements for physical activity compared with their male peers in adolescence and early adulthood. As teenagers, 88 percent of boys and 78 percent of girls were physically active. But as they left gym class and school sports behind and transitioned into adulthood, these numbers dropped to 73 percent of young men and 62 percent of young women reporting getting any moderate or vigorous physical activity, according to the new study. The data also revealed that being of a minority race or ethnicity or having a low income were also associated with a lower level of physical activity in most groups. The researchers analyzed data gathered by the National Health and Nutrition Examination Survey, which surveyed 9,472 teens and young adults in the United States about their exercise habits at multiple intervals between 2007 and 2016. These disparities are a problem, says Kelly Evenson, PhD, a research professor in the department of epidemiology at the University of North Carolina’s Gillings School of Global Public Health in Chapel Hill, North Carolina (who was not involved in the new study). “These differences have been identified across the life span, but they seem to diverge to a greater extent as girls transition to middle school.”

Women, Minorities, and Low-Income Young Adults Are Exercising Less Than Others

Adolescence and early adulthood are a critical time for young people to develop healthy habits that decrease their lifelong risk for type 2 diabetes, cancer, obesity, and cardiovascular diseases. The 2008 Physical Activity Guidelines for Americans recommend 60 minutes of exercise per day for adolescents ages 6 to 17 (420 minutes per week) and 150 minutes of exercise per week for adults. The authors of the study noted that the decline in physical activity for both men and women was steepest between the teenage years and early adulthood (ages 18 to 24). They suggested that this decline might be due to the increased demands of employment and higher education during early adulthood. But why were young women less physically active than men? Only a third of women ages 25 to 29 met the weekly recommendations, according to the new data. “Our research did not explore the reasons, so we don’t know the why from this study,” says Eliana Perrin, MD, a co-author of the study and a professor of pediatrics at the Duke University School of Medicine, and the director of the Duke Center for Childhood Obesity Research, both in Durham, North Carolina. “However, it does seem that there are cultural barriers to physical activity for women and less encouragement by society to be active and vigorous.” Dr. Perrin goes on to say, “Concerns about image and appearance have been cited by adolescents and young adults as reasons for not exercising.” The study also found that young women of color were even less likely to meet the recommendations for physical activity. Seventy percent of black teenage girls were physically active, but only 45 percent of black women ages 18 to 24 reported any physical activity at all. Hispanic female adolescents were physically active for shorter periods of time than their white peers. Black males ages 18 to 24, however, reported the longest duration of physical activity. Overall, younger, higher income, and white individuals reported the highest amount of physical activity. Higher education level was found to be associated with increased physical activity. Other research has confirmed the association between poverty and physical inactivity. This study, however, found that men with lower income were just as active as their high-income peers.

One Limitation Is That the Data Was Self-Reported

The study’s authors admit that there are obvious limitations to a survey where participants are asked to make their best guess about how physically active they are. Also, they note that it’s difficult to report the relationship between income and physical activity when many young adults in college may report less income while being supported by a high-income family. It’s also important to note that the study was cross-sectional, not longitudinal. That means the researchers compared exercise habits in different age groups of individuals at multiple points over the course of the study, but didn’t follow the same individuals over the course of the study. Regardless, the new data points to the need to remove barriers that keep women, racial and ethnic minorities, and individuals experiencing poverty from being active. “Communities need to recognize that gym memberships and sports equipment aren’t cheap, and poor neighborhoods are less likely to have safe spaces for activity or even sidewalks or bike trails,” says Perrin. “Whatever communities can do to encourage active living would be a step in the right direction. What we are seeing from our study is that policies, spending, and research should be focusing on disparities in physical activity so all youth can be healthy.” For those looking to encourage kids to stay physically activity long into adulthood, Dr. Evenson recommends that communities look at schools, parks, and the overall environment to provide more opportunities. She suggests that schools in particular consider how they can help with the transition to a healthy adulthood. “They can educate students on how to continue a lifetime of physical activity, with strategies and skills on negotiating barriers that can get in the way of being physically active,” Evenson says.